Footwear with removable bootie

ABSTRACT

A footwear construction is provided including a primary footwear component and a secondary footwear component removably disposed in the primary footwear component. The primary footwear component can include an inward facing wall, and the secondary footwear component can include an outward facing wall surrounding a secondary sole of the secondary footwear component. The inward facing wall is configured to releasably interlock with the outward facing wall, such that the secondary sole is secured within the primary footwear component, yet can be manually pulled upward, whereby the inward facing wall releases from the outward facing wall to enable the secondary footwear component to be removed completely from the primary footwear component.

BACKGROUND OF THE INVENTION

The present invention relates to footwear, and more particularly to footwear having a removable bootie that is able to function as a separate footwear article.

There are a variety of different types of footwear that serve different functions. Some footwear is designed for rigorous outdoor activity. This footwear can include heavy duty structural uppers and outsoles configured to withstand extensive engagement with an outdoor environment. Other footwear is designed for casual indoor activity. This footwear can include more flexible uppers and minimalistic outsoles, particularly where the footwear is to be utilized in an indoor casual or nonathletic activity.

Some manufacturers have tried to produce footwear that can be modified for function in both rigorous outdoor activities and casual indoor activities. This footwear can include an outer footwear and an internal slipper that is removable from the outer footwear. The internal slipper can be worn inside the outer footwear, while the outer footwear is utilized in an outdoor activity. When the user goes inside and desires to engage in a leisurely activity, the user can remove the internal slipper from the outer footwear and wear the slipper alone.

While the above footwear, having an internal slipper removable from an outer footwear, is useful it suffers several shortcomings. For example, the internal slipper frequently can slide around in and/or move within the outer footwear due to no connection between the slipper and the outer footwear. In turn, a user can experience unstable footing when wearing the combination footwear. Further, the slipper can become misplaced and/or bunch within the outer footwear, which can cause discomfort to the wearer. In addition, in particularly rigorous activities, if the slipper is not secured properly, the outer footwear can disengage the internal slipper and become unintentionally removed from the wearer's foot, while the slipper remains in place. Lastly, the internal slipper typically lacks sufficient underfoot cushioning. Thus, when an indoor activity is performed on hard floors, the internal slipper might not provide sufficient cushioning for the user.

Accordingly, there remains room for improvement in the field of multi-use footwear including a combination of nested footwear configured for different activities.

SUMMARY OF THE INVENTION

Footwear is provided including a primary footwear component and a secondary footwear component removably disposed in the primary footwear component.

In one embodiment, the primary footwear component includes an inward facing wall, and secondary footwear component includes an outward facing wall surrounding a portion of a secondary sole of the secondary footwear component. The inward facing wall is configured to releasably interlock with the outward facing wall, such that the secondary sole can be manually pulled upward, whereby the inward facing wall release the outward facing wall to enable the secondary footwear component to be removed completely from the primary footwear component. The secondary footwear is then operable and wearable independent from the primary footwear.

In another embodiment, the inward facing wall and the outward facing wall can be angled toward a longitudinal axis of the footwear. These walls can be angled at the same or different angles, optionally acute angles, relative to that axis. In some cases, the walls can be angled relative to a reference line at a bottom of a recess of the primary footwear component. The angle can be an acute angle, optionally in the range of 5° to 89°, inclusive, further optionally in a range of 5° to 45°, inclusive, even further optionally in a range of 10° to 30°, inclusive, and yet further optionally in a range of 15° to 20°, inclusive.

In still another embodiment, portions of the inward facing wall and outward facing wall of the respective components can be associated with respective primary sole and secondary sole. These soles can be constructed from a rigid yet flexible material, such as a cushioning material, for example ethyl vinyl acetate, a polyurethane foam, thermoplastic polyurethane and/or other materials.

In even another embodiment, the primary sole can be constructed so that the inward facing wall is structured and/or configured to flex outwardly, away from the longitudinal axis of the footwear, when the secondary sole is pulled upward and away from the primary sole. This flexing can enable the secondary sole to escape and release from a recess defined in the primary sole.

In yet another embodiment, the inward facing wall and/or outward facing wall can be partially or fully rounded. For example on the lateral and medial sides of the footwear, adjacent an area where the ball or forefoot of a wearer will be disposed, the inward facing wall and outward facing wall each can be rounded so that these elements can interlock with one another. For example, the outward facing wall can be convex, while the inward facing wall can be concave so that the walls seat within one another, and can be releasably interlocked with one another in that location.

In a further embodiment, the inward facing wall and/or outward facing wall can have similar or different surface contours. For example is one example, the outward facing wall can include a rounded and/or semicircular contour, while the inward facing wall can be a flat or generally planar wall. With this construction, the outward facing wall can easily slide up and out of engagement with the rounded contour of the inward facing wall. As another example, the outward facing wall can include a planar contour, and the inward facing wall can include a similar planar contour. With these constructions of the walls, the walls can shift and move relative to one another, with there being minimal interlocking of their surfaces other than a friction fit of the secondary component and the primary component. As yet another example, the inward facing wall can be angled inwardly from bottom to top relative to a longitudinal axis of the footwear, while the outward facing wall can be rounded such that it can be interlocked by an upper lip of the angled inward facing wall.

In still a further embodiment, the primary sole component can include an upper and/or an outsole having a window defined therein. The window can be completely open, or can be covered with a translucent and/or transparent material. With the open window, or the translucent or transparent window, when the secondary footwear component is disposed in the primary footwear component, portions of that secondary footwear component are visible through the window to a wearer or observer of the footwear.

In still yet a further embodiment, the secondary footwear component can include a secondary sole that includes its own independent outsole. This outsole can provide and/or include a cushion layer to provide underfoot cushioning to the footwear component. Thus, when the secondary footwear component is removed from the primary footwear component, it can operate and function as an independent footwear unit, worn by the wearer. It also can provide satisfactory cushion to the wearer's foot.

In even a further embodiment, the secondary footwear component can include a secondary sole that mechanically interlocks with a primary sole of the primary footwear component. The mechanical interlock can include portions of an inward facing wall of the primary footwear component and of an outward facing wall of the secondary footwear component. These walls could be specially shaped so that they do not become free relative to one another without the application of a predetermined force to remove the walls coming engagement from one another. This force can range from 1 pound to 10 pounds, inclusive; further optionally to pounds to 8 pounds, inclusive yet further optionally 3 pounds to 5 pounds, inclusive and/or other forces depending on the application.

In yet still another embodiment, the primary component can include a Strobel construction, with a primary upper joined to a primary sole. A Strobel board can be joined with the primary upper. The Strobel board can be below the secondary sole and above the primary sole.

The footwear of the current embodiments provides a multifunctional footwear having one type of footwear inside another type of footwear. The different types of footwear can be utilized in different activities. The outer footwear component can be constructed for more rigorous activities, optionally while the inner footwear component is disposed therein. The inner footwear component can be releasably removed from the outer footwear component, and can be more minimalist, yet still enable the user to wear the inner footwear in particular environments. Where the inner footwear component also includes cushioning, it can provide adequate comfort to a wearer when being worn alone. The interlock structures also selectively keep the footwear components connected during activity, yet enable a user to disengage the footwear components when it is suitable to use one or more of them independently.

These and other objects, advantages, and features of the invention will be more fully understood and appreciated by reference to the description of the current embodiment and the drawings.

Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited to the details of operation or to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention may be implemented in various other embodiments and of being practiced or being carried out in alternative ways not expressly disclosed herein. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof. Further, enumeration may be used in the description of various embodiments. Unless otherwise expressly stated, the use of enumeration should not be construed as limiting the invention to any specific order or number of components. Nor should the use of enumeration be construed as excluding from the scope of the invention any additional steps or components that might be combined with or into the enumerated steps or components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of footwear of a current embodiment illustrating a secondary footwear component being removed from or installed in a primary footwear component;

FIG. 2 is a side view of the footwear with the secondary footwear component fully installed in the primary footwear component;

FIG. 3 is a rear view of the secondary footwear component including a portion of an interlocking feature;

FIG. 4 is another rear perspective view thereof;

FIG. 5 is yet another rear perspective view thereof;

FIG. 6 is a section view of the footwear taken along lines 6-6 of FIG. 2;

FIG. 7 is a section view of the footwear taken along lines 7-7 of FIG. 2;

FIG. 8 is a partial section view of a first alternative embodiment of the footwear;

FIG. 9 is a partial section view of a second alternative embodiment of the footwear; and

FIG. 10 is a partial section view of a third alternative embodiment of the footwear.

DESCRIPTION OF THE CURRENT EMBODIMENTS

A current embodiment of the footwear is illustrated in FIGS. 1-7, and generally designated 10. This footwear generally includes a primary footwear component 20 having a primary upper 21 and a primary sole 22 that cooperatively define a void 23 within which a secondary footwear component 40 is removably disposed. The secondary footwear component can include a secondary sole 42 and a secondary upper 41. The secondary footwear component can function as footwear independently and removed from the primary footwear component as described below. The first and second footwear components can include interlocking features 60, as shown in FIG. 6, that maintain the secondary footwear component in a generally fixed and locked, or secured relationship relative to the primary footwear component when the secondary for component is disposed in the primary footwear component.

Although the current embodiments are illustrated in the context of a winter boot or water resistant shoe, they may be incorporated into any type or style of footwear, including performance shoes, hiking shoes, trail shoes and boots, hiking boots, work boots, all-terrain shoes, barefoot running shoes, athletic shoes, running shoes, sneakers, conventional tennis shoes, walking shoes, multisport footwear, casual shoes, dress shoes or any other type of footwear or footwear components. It also should be noted that directional terms, such as “vertical,” “horizontal,” “top,” “bottom,” “upper,” “lower,” “inner,” “inwardly,” “outer” and “outwardly,” are used to assist in describing the invention based on the orientation of the embodiments shown in the illustrations.

Further, the terms “medial,” “lateral” and “longitudinal” are used in the manner commonly used in connection with footwear. For example, when used in referring to a side of the shoe, the term “medial” refers to the inward side (that is, the side facing the other shoe) and “lateral” refers to the outward side. When used in referring to a direction, the term “longitudinal direction” refers to a direction generally extending along the length of the shoe between toe and heel, and the term “lateral direction” refers to a direction generally extending across the width of the shoe between the medial and lateral sides of the shoe. The use of directional terms should not be interpreted to limit the invention to any specific orientation. Further, as used herein, the term “arch region” (or arch or midfoot) refers generally to the portion of the footwear or sole assembly corresponding to the arch or midfoot of the wearer's foot; the term “forefoot region” (or forefoot) refers generally to the portion of the footwear forward of the arch region corresponding to the forefoot (for example, including the ball and the toes) of a wearer's foot; and the term “heel region” (or heel) refers generally to that portion of the footwear rearward of the arch region corresponding to the heel of the wearer's foot. The forefoot region 17, arch region or mid-foot region 18 and heel region 19 generally are identified in FIG. 2. However, it is to be understood that delineation of these regions may vary depending upon the configuration of the sole assembly and/or footwear.

With reference to FIG. 2, the primary footwear component 20 can include a primary sole 22. The sole 22 can be configured to include a ground contacting surface 23 which itself may include multiple lugs, treads, spikes, cleats and/or other features designed to enhance traction between the footwear 10 and in underlying surface. The sole 22 can include one or more different components, such as an outsole, a midsole and/or an insole. Generally, regardless of which components are present, the primary sole can form the bottommost portion of the primary footwear component 20.

As shown in FIGS. 2 and 6, the primary sole 22 is joined with the primary upper 21. The primary upper can include a vamp 21V, a toe box 21B, quarter panels 21Q and a heel portion 21H. These components may be joined with one another as integral parts of a single piece upper, or they can be joined together with fasteners such as stitching, glue or other features. The primary sole joined with the primary upper can cooperatively define a primary void 23 within which all or a portion of the secondary footwear component 40 removably interfits and/or nests.

With further reference to FIGS. 2 and 6, the primary sole 22 can include an upper surface 24. This upper surface generally can be the highest point, surface or region, on the primary sole 22 in any given cross-section taken transverse to the longitudinal axis LA of the footwear 10. The primary sole 22 also can define a recess 22R that extends downwardly from the upper surface 24 to a recess bottom 26. Between the upper surface 24 and the bottom 26 is disposed an inward facing wall 25. This inward facing wall 25 optionally can include a lower peripheral allowance 21L of the primary upper 21, where the allowance 21L is glued, fastened, molded or otherwise attached to the sole 22 and optionally can form a portion of that inward facing wall 25. For purposes herein, the inward facing wall can be the actual interior surface 25 of the outsole itself, and/or the interior surface of the allowance 21L, or some other component inward from the same. This inward facing wall 25 extends downward to the recess bottom 26.

Optionally, the inward facing wall 25 can be contoured so that the inward facing wall 25 engages and secures and/or interlocks with and outward facing wall 45 of the secondary sole 42 or some other portion of the secondary footwear component 40. As an example, the inward facing wall 25 can include a first wall portion 25A that is inward angled toward a longitudinal axis LA of the footwear, from a lower part 25L of the first wall portion 25 to an upper part 25U of the first wall portion 25. In this construction, the upper part 25U of the first wall portion can be closer to the longitudinal axis LA than the lower part 25L of the first wall portion 25. Further, where the first wall portion 25A is disposed on the lateral L and medial M sides of the footwear, for example, by virtue of it extending around at least a portion of the heel region 19 of the of the footwear, the width of the recess 22R in that location adjacent the lower part 25L can be a width W1. Likewise the distance between the upper parts 25U on opposite medial and lateral sides can be a width W2. The width W1 can be greater than the width W2. As an example, the width W1 can be optionally 1 mm, further optionally 2 mm, even further optionally 3 mm, yet further optionally 5 mm, still further optionally 10 mm or more than the width W2. Of course, in some applications, the width W1 can be less than the width W2 in corresponding amounts.

With reference to FIG. 6, the first wall portion 25 again can be inward angled relative to the longitudinal axis LA from the lower part 25L to the upper part 25U. This angle A1 can be an acute angle, and can be measured relative to the primary reference line PRL that is coincident with lowermost part of the bottom 26 of the recess 22R. This angle A1 can be in the range of 5° to 89°, inclusive, further optionally in the range of 10° to 30°, inclusive, yet further optionally in the range of 15° to 20°, inclusive. This acute angle A1 can be referred to as a first angle of the first wall portion 25 of the primary sole 22. Of course other angles can be selected is desired. Further is to be appreciated that this angle A1 can refer to the angle taken tangent to a fully or partially curved surface of the inward facing wall, and in particular the first wall portion 25. In addition, although the inward facing wall can be described as angled, it also can include one or more planar, convex, concave and/or rounded surfaces.

Optionally, the width of the recess, as mentioned above can vary. Adjacent the upper part 25U, the width of the recess 22R can be of a width W2. Adjacent a lower part 25L, the width can be W1, which can be greater than width W2. Further optionally, immediately adjacent the bottom of the recess, the width can be a width W5 which is less than the width W1 at the lower part 25L and less than the width W2 at the upper part 25U. Of course, these widths can vary, but generally the width W1 can be greater than the width W2 to provide some sort of interlocking feature with the inward facing wall.

As also shown in FIG. 6, the primary upper 21 can be joined with a Strobel board 28 adjacent a primary lower peripheral allowance 21L of the primary upper. The Strobel board can be disposed above the primary sole and above the bottom 26 of the recess 22R. In the illustrated construction, Strobel board 28 also can be disposed under the secondary sole 42 and in particular its lowermost surface 42B, which again can function as a ground contacting surface when the secondary footwear component 40 is removed from the primary footwear component 20.

The secondary footwear component 40 will now be described in more detail with reference to FIGS. 3-6. The secondary footwear component 40 can include its own upper 41 and its own dedicated sole 42. The upper as shown can be a knitted component. An optional knitted upper is disclosed in pending U.S. patent application Ser. No. 15/648,514 to Burch, filed Jul. 13, 2017, which is incorporated by reference in its entirety herein. This knitted upper optionally can include a cushion element disposed underfoot, between knitted layers. Of course, other types of uppers can be utilized with the secondary footwear component. The outsole 42 can include its own ground contacting surface 43 so that when the secondary component is removed from the primary component, the secondary component can function similar to regular footwear. The secondary footwear component, in particular the secondary upper 41 and secondary sole 42 can cooperatively defined a secondary void 44 which is configured to receive the foot of a wearer. Secondary footwear component and optionally the secondary sole 42 can include an outward facing exterior wall 45 that extends downwardly adjacent a lower portion 41L of the secondary upper 41. The outward facing wall 45 can include a second wall portion 45A that is inward angled toward a longitudinal axis LA of the footwear 10 from a lower part 45L of the second wall portion 45A to an upper part 45U of the second wall portion. The upper part 45U of the second wall portion can be closer to the longitudinal axis LA than the lower part 45L of the second wall portion. This second wall portion 45A optionally can extend around at least a portion of the periphery of the secondary sole 42.

As shown, the outward facing wall 45 extends primarily and/or substantially only in the heel region 19 of the footwear. It can be strategically placed here in some applications to enhance the interlock of the heel region of the secondary footwear component within the primary footwear component and its recess. This can be suitable to prevent the removal of the secondary footwear component from the primary footwear component due to the heel being pulled to forcefully from the primary footwear component, particularly where the primary footwear component may be lodged or stuck in underlying terrain, for example, mud, snow or the like. This also can prevent the heel part of the secondary component from being dislodged from the heel part of the primary or component when moisture is disposed between those elements due to perspiration and/or liquids that may enter the footwear 10.

With reference to FIG. 6, the second wall portion 45A again can be inward angled relative to the longitudinal axis LA from the lower part 45L to the upper part 45U. The angle optionally can be an acute angle A2, and can be measured relative to the primary reference line PRL that is coincident with a bottom of the recess 22R. This angle A2 can be in the range of 5° to 89°, inclusive, further optionally in the range of 10° to 30°, inclusive, yet further optionally in the range of 15° to 20°, inclusive. This acute angle A2 can be referred to as a second angle of the second wall portion 45A of the secondary sole component. Of course other angles can be selected is desired. Further, is to be appreciated that this angle A2 can refer to an angle taken tangent to a partially or fully curved surface of the outward facing wall 45, in particular the second wall portion 45A. In addition, although the inward facing wall can be described as angled, it also can include one or more planar, convex, concave and/or rounded surfaces. Further optionally, the second angle A2 can be equal to the first angle A1. In other cases, these angles can be different, with one being more acute or obtuse than the other. In yet other cases, the angles can be perpendicular or parallel to the recess bottom 26.

Optionally, the width of the secondary sole 42, as mentioned above can vary. Adjacent the upper part 45U the width of the secondary sole 42 can be of a width W4, shown in FIG. 6. Adjacent a lower part 45L, the width can be W3 which can be greater than width W4. Further optionally, immediately adjacent the bottom of the recess 22R the secondary sole can be a width W6 which can be less than the width W3 at the lower part 45L and less than the width W4 at the upper part 45U. Of course, these widths can vary but generally the width W3 can be greater than the width W4 to provide some sort of interlock feature between the outward facing wall and the inward facing wall. It will be further appreciated that the widths of the recess W1, W2 and W5 can be approximately equal to or slightly greater than the widths W3, W4 and W6 of corresponding parts of the secondary sole 42 in the various locations and distances from the bottom of the recess.

As shown in FIG. 6, the outward facing wall 45 of the secondary sole can be placed immediately adjacent and optionally engaging the inward facing wall 25 of the primary sole 22. Secondary sole 42 also can be placed at least partially within or fully within the recess 22R of the primary sole 22. Generally, when the inward facing wall and outward facing wall of the interlock feature 60 are configured as shown in FIG. 6, the upper part 25U of the first wall portion 25A engages the upper part 45U of the second wall portion 45A to interlock the secondary sole 42 within the recess 22R of the primary sole 22, particularly when the secondary upper and the secondary sole are disposed in the void 23 cooperatively formed by the primary sole and the primary upper.

To enable removal of the secondary component from the primary component, the interlocking feature 60 can be releasable. To provide a release mechanism of the interlocking feature 60 and thereby enable removal of the secondary footwear component from the primary footwear component, the primary footwear component and/or secondary footwear component can be configured to flex, bend, slide, move or otherwise displace relative to one another. As one example, the upper part 25U of the first wall portion 25A can be configured to flex or bend in direction B, generally away from the longitudinal axis LA, when the secondary sole 42 is urged upwardly under a force F. This in turn pulls the secondary sole 42 away from the primary sole 22 so the secondary upper and secondary sole can be removed from the primary upper and the primary sole, respectively. After this removal, the secondary footwear component 40 can be utilized as a separate and independent footwear from the primary footwear component 20. Of course, the secondary footwear component can be replaced back into the void 23 of the primary footwear component in the opposite manner.

Optionally, in some constructions, the outward facing wall can transition to an undercut wall 45X. This undercut wall can be disposed at an obtuse angle A3 relative to the primary reference line PRL. With this obtuse angle, the undercut wall can assist in bending the upper part 25U of the first wall portion 25A outward and away from the longitudinal axis LA so that the inside facing wall 25 can interlock with the outward facing wall 45 again as shown in FIG. 6, where the primary and secondary components are configured together in the combination footwear. Further optionally, upon this interlock, when the upper part 25U bends back inward towards the longitudinal axis, it can emit an audible sound, such as a snap or click, to alert the wearer that the secondary footwear component has been adequately installed in the primary footwear component. This click or snap can be created via the slapping of the outward facing wall 45 against the inward facing wall 25 in some cases.

As mentioned above, the interlocking feature 60 can be disposed primarily in the heel region 19, and in some cases in the arch region 18 as well. Of course, optionally, that feature 60 can be disposed around the entire periphery of the footwear components, or intermittently spaced about the same and/or in different regions. In the currently embodiment, forward of the heel region, for example in the forefoot region 17, the profile or contours of the inward facing wall and the outward facing wall can be different. For example, as shown in FIG. 7, the outward facing wall 65 of the secondary sole component 42 can be rounded and/or obtusely angled relative to the primary reference line PRL at angle A4 Likewise the inward facing wall 55 also can be outwardly angled at a similar obtuse angle A5. These walls 55 and 65 can transition to corresponding walls 25 and 45 in the heel region. Further, the width W8 of the recess 22R and secondary sole as well as in the upper parts thereof can be wider than the widths W9 of the same adjacent the bottom of the recess 22R. This construction can be suitable in the forefoot so that portion of the secondary sole can slide or move relative to the corresponding forefoot portion of the primary footwear component, during a gait cycle. This construction, with minimal or no dedicated interlock features 60 in the forefoot region 17 also can facilitate removal or sliding of the secondary component out of the corresponding part of the primary component.

Optionally, the primary footwear component 20 can define a window 29. The window can be without a covering, so that it is a through hole, or it can include a transparent or translucent covering. The secondary footwear component 40 can include an indicia or feature 49. This element 49 is disposed on the secondary component 40 so that when the secondary component is installed in the primary component, the element 49 is viewable to the wearer or a wearer through the window 29.

A first alternative embodiment of the footwear is illustrated in FIG. 8 and generally designated 110. This footwear can be similar in structure, function and operation to the embodiment described above with several exceptions. For example, this footwear 110 can include a primary footwear component 120 and a second footwear component 140. The primary footwear component 120 can include an upper 121 that is joined to an outsole or primary sole 122. This joining can be of via a stitching 122S through a lower peripheral allowance of the upper. The secondary footwear component can include a secondary upper 141 having a Strobel board 149 closing its bottom. The secondary upper can be joined with the secondary sole 142. The secondary sole 142 can include an outward facing wall 145 that engages in inward facing wall 125 of the primary footwear component. Both walls can be substantially planar, with the sole recess 122R and secondary sole 142 being wider at the bottom than at the top of the same. The interface or engagement of the inward facing wall and outward facing wall of the different components can provide interlock structure similar to that of the embodiment above.

A second alternative embodiment of the footwear is illustrated in FIG. 9 and generally designated 210. This footwear can be similar in structure, function and operation to the embodiment described above with several exceptions. For example, this footwear 210 can include a primary footwear component 220. The primary footwear component 220 can include a sole component 221 including an inward facing wall 225 that terminates at an upper part 225U which itself curves inwardly. The middle part 225M of that wall can be generally vertical. The secondary sole 242 can include an outward facing wall 245 that is generally rounded and/or partially convex. The rounded portion can interfere with the inwardly projecting rounded upper portion 225U of the primary footwear component to assist in interlocking these features together and holding the secondary footwear component within the primary footwear component.

A third alternative embodiment of the footwear is illustrated in FIG. 10 and generally designated 310. This footwear can be similar in structure, function and operation to the embodiment described above with several exceptions. For example, this footwear 310 can include a primary footwear component 320 and a secondary footwear component 340. The primary footwear component 320 can include a sole component 321 including in inward facing wall 325. This inward facing wall 325 can be generally concave. The corresponding outward facing wall 325 can be correspondingly shaped and can be generally convex. With these contours, the concave portion can releasably receive the convex portion to interlock the secondary footwear component with the primary footwear component. The upper part 325U of the primary sole 322 can be flexible and optionally can be substantially vertical, as can be a corresponding part of the secondary sole 342. Optionally, the lower part 325L of the secondary sole and a corresponding portion of the primary sole can be substantially vertical as illustrated. Thus, the inward facing wall portion and outward facing wall portions can have different contours from top to bottom of each.

Directional terms, such as “vertical,” “horizontal,” “top,” “bottom,” “upper,” “lower,” “inner,” “inwardly,” “outer” and “outwardly,” are used to assist in describing the invention based on the orientation of the embodiments shown in the illustrations. The use of directional terms should not be interpreted to limit the invention to any specific orientation(s).

The above description is that of current embodiments of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. This disclosure is presented for illustrative purposes and should not be interpreted as an exhaustive description of all embodiments of the invention or to limit the scope of the claims to the specific elements illustrated or described in connection with these embodiments. For example, and without limitation, any individual element(s) of the described invention may be replaced by alternative elements that provide substantially similar functionality or otherwise provide adequate operation. This includes, for example, presently known alternative elements, such as those that might be currently known to one skilled in the art, and alternative elements that may be developed in the future, such as those that one skilled in the art might, upon development, recognize as an alternative. Further, the disclosed embodiments include a plurality of features that are described in concert and that might cooperatively provide a collection of benefits. The present invention is not limited to only those embodiments that include all of these features or that provide all of the stated benefits, except to the extent otherwise expressly set forth in the issued claims. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular. Any reference to claim elements as “at least one of X, Y and Z” is meant to include any one of X, Y or Z individually, and any combination of X, Y and Z, for example, X, Y, Z; X, Y; X, Z; and Y, Z. 

1. An article of footwear comprising: a primary upper, a primary sole joined with the primary upper so that the primary upper and the primary sole cooperatively define a primary void, the primary sole including an upper surface and a recess extending downward from the upper surface, the recess bounded by an inward facing wall that includes a first wall portion inward angled toward a longitudinal axis of the footwear from a lower part of the first wall portion to an upper part of the first wall portion adjacent the upper surface, such that the upper part of the first wall portion is closer to the longitudinal axis than the lower part of the first wall portion, a secondary upper, and a secondary sole joined with the secondary upper so that the secondary upper and the secondary sole cooperatively define a secondary void, the secondary void configured to receive the foot of a wearer, wherein the secondary upper and secondary sole are removably nested within the respective primary upper and the primary sole, wherein the secondary sole includes an outward facing exterior wall that extends downwardly adjacent the secondary upper, the outward facing exterior wall including a second wall portion inward angled toward a longitudinal axis of the footwear from a lower part of the second wall portion to an upper part of the second wall portion, such that the upper part of the second wall portion is closer to the longitudinal axis than the lower part of the second wall portion, wherein the outward facing wall of the secondary sole is placed immediately adjacent the inward facing wall of the primary sole and the secondary sole is placed at least partially within the recess of the primary sole, wherein the upper part of the first wall portion is configured to engage the upper part of the second wall portion to interlock the secondary sole within the recess of the primary sole when the secondary upper and secondary sole are disposed in the void cooperatively formed by the primary sole and the primary upper, wherein the upper part of the first wall portion is configured to flex away from the longitudinal axis when the secondary sole is urged upwardly away from the primary sole so that the secondary upper and secondary sole can be removed from the primary upper and the primary sole.
 2. The article of footwear of claim 1, wherein the primary upper is joined with a Strobel board adjacent a primary lower peripheral allowance of the primary upper, wherein the Strobel board is disposed under the secondary sole and above the primary sole.
 3. The article of footwear of claim 2, wherein the secondary sole includes a second bottom surface, wherein the second bottom surface transitions to the lower part of the second wall portion, wherein the second wall portion is substantially parallel to the first wall portion when the secondary sole is disposed in the recess of the primary sole.
 4. The article of footwear of claim 3, wherein the primary sole includes a primary reference line coincident with a bottom of the recess, wherein the outward facing wall of the secondary sole is disposed at a first acute angle relative to the primary reference line, wherein the inward facing wall of the primary sole is disposed at a second acute angle relative to the primary reference line.
 5. The article of footwear of claim 4, wherein the first acute angle and the second acute angle are equal.
 6. The article of footwear of claim 1, wherein the primary sole includes a primary reference line coincident with a bottom of the recess, wherein the outward facing wall of the secondary sole is disposed at a first acute angle relative to the primary reference line, wherein the inward facing wall of the primary sole is disposed at a second acute angle relative to the primary reference line, wherein the first acute angle is in the range of 5° to 89°, inclusive.
 7. The article of footwear of claim 6, wherein the first acute angle is in the range of 10° to 30°, inclusive.
 8. The article of footwear of claim 6, wherein the first acute angle is in the range of 15° to 20°, inclusive.
 9. The article of footwear of claim 1, wherein the first wall portion transitions to a third wall portion that is at least one of substantially vertical and rounded between the upper surface and a bottom of the recess.
 10. The article of footwear of claim 1, wherein the primary upper includes a window through which the secondary upper can be viewed when the secondary upper and secondary sole are disposed in the void.
 11. An article of footwear comprising: a primary upper joined with a primary sole to form a primary footwear component; a secondary upper joined with a secondary sole to form a secondary footwear component, the secondary footwear component removably disposed in the primary footwear component, wherein the primary footwear component includes an inward facing wall, wherein the secondary footwear component includes an outward facing wall configured to frictionally engage the inward facing wall to interlock the secondary footwear component with the primary footwear component, wherein the inward facing wall is configured to flex outward when the secondary sole is pulled upward, thereby releasing the secondary sole from the primary sole to enable the secondary footwear component to be removed completely from the primary footwear component.
 12. The article of footwear of claim 11, wherein the inward facing wall extends around a recess configured to receive the secondary sole, wherein the outward facing wall extends around an outer periphery of the secondary sole in substantially a heel region of the footwear.
 13. The article of footwear of claim 12, wherein the recess includes a recess bottom and a recess top, the recess top being adjacent an upper surface of the primary sole, wherein the recess is wider below the recess top than at the recess top.
 14. The article of footwear of claim 13, wherein the outward facing wall includes a lower surface and an upper surface of the secondary sole, wherein the secondary sole is wider adjacent the lower surface than at the upper surface of the secondary sole.
 15. The article of footwear of claim 11, wherein the primary sole includes a primary reference line coincident with a bottom of the recess defined by the primary sole, wherein the outward facing wall of the secondary sole is disposed at a first acute angle relative to the primary reference line, wherein an inward facing wall of the primary sole is disposed at a second acute angle relative to the primary reference line, wherein the first acute angle is in the range of 5° to 89°, inclusive.
 16. The article footwear of claim 15, wherein the outward facing wall and the inward facing wall are parallel, wherein the first acute angle is equal to the second acute angle.
 17. The article of footwear of claim 15, wherein the first acute angle is in the range of 10° to 20°, inclusive wherein the second acute angle is in the range of 5° to 45°, inclusive.
 18. The article of footwear of claim 11, wherein the primary footwear component includes at least one of a translucent window and a transparent window, wherein the secondary footwear component includes an exterior surface, wherein the exterior surface is visible through the at least one of a translucent window and a transparent window of the primary footwear component.
 19. An article of footwear comprising: a primary footwear component; a secondary footwear component removably disposed in the primary footwear component, wherein the primary footwear component includes an inward facing wall, wherein the secondary footwear component includes an outward facing wall surrounding a heel region of a secondary sole of the secondary footwear component, wherein the inward facing wall is configured to releasably interlock with the outward facing wall, such that when the secondary sole is pulled upward, the inward facing wall releases from the outward facing wall to enable the secondary footwear component to be removed completely from the primary footwear component.
 20. The method of claim 19, wherein the inward facing wall includes an upper part and a lower part, the upper part being closer to a longitudinal axis of the footwear than the lower part of the inward facing wall, wherein the outward facing wall includes an upper part and a lower part, the upper part being closer to a longitudinal axis of the footwear in the lower part of the outward facing wall. 